Bleeder or purging apparatus for refrigerating systems



52151.24, 1940. T. Hr REA 2,215,717

BLEEDER OR IURGING APPARATUSFOR REFRIGERATIG SYSTEMS Filed Feb. 17, 1959zsneets-sheez 1 IN VENT OR.

` `7150/7706 /7. /cea BY @www ATTORNEYS sq. 24, 1940. T`., REA`2,215,717

BLEEDER 0R PURGING APIARATUS FOR REFRIGERATING SYSTEMS Filed Feb. 17,1939 2 Sheets-Sheet? 1N VENTOR.

Patented Sept. 24, 1940 1 AT1-11-1T` ori-ice BLEEDER on PURGINGAPPARATUS Foa REFRIGERATING SYSTEMS Thomas I-I.` Rea, ThreeRiveravMich., assignor to Armstrong Machine Works, Three Rivers, Mich.,

a corporation of Michigan Application February 17, 1939, serial No.257,027

11 Claims.

This invention relates to improvements in bleeders or purging apparatusvfor refrigerating systems;

The main objects of this invention are:

First, `to provide an automatic purging or bleeding apparatus forrefrigerating systems which is highly efficient, entirely automatic inits operation, and is not likely tobecome inoperative in use. e

, Second, to provide a purging apparatus which, when once set intooperation, requires no `manual manipulation. e

Third, to provide an apparatus having these advantages which may be usedas a. so-called straight purging unit or may be `used as `a combinedexpansion valve and purgerunit. I

Fourth, to provide an apparatus having these advantages which isverycompact and has rela` tively few movable parts.

Objectsv relating to' details and economies of the invention will appearfrom the description to follow. The invention is defined and" pointedout` in the claims.

Preferred embodiments of the invention are illustrated in theaccompanying drawings, in which:

Figl represents a. refrigerating system `mainly in diagrammatic ,form inwhich the apparatus of my inyerit on is installed to serve as a combined expansion valve and purger. e I

Fig. 21is anl enlarged fragmentary view mainly in vertical section online 2-2 of Fig. 4.

Fig.1 3 isa fragmentary view partially in vertical section on line 3-3of Fig. 4.

Fig. 4 isa view mainly in horizontal section on line "4-4 of Fig. 2.

Fig. 5 is a view mainly in diagrammatic form showing Imy improvedpurging apparatus installed as a straight purging unit or apparatus.

In the installation shown in Fig. 1, I designates the compressor, 2 acondenser, 3 the evaporating coils, and 4 the surge drum of arefrigerating apparatus in connection with which I have shown my purgingapparatus which is designated generally by the numeral 5.

This purging apparatus, in the preferred embodiment illustrated,comprises an inlet chamber 6 to which the supply connection 1 delivers,this supply connection being preferably provided with a valve B. Itwillbe noted that the supply pipe 1 has a delivery nipple 9 projectingcentrally of the inlet chamber and terminating in a valve seat for` thenon-returncheclr` valve I Above this inlet chamber isa separazingchamber II open at its lower end to the upper end of the inlet chamber.This chamber II is surrounded by a jacket I2 forming a refrigerating 1chamber I3 surrounding the separating chamber, the wall I4 of theseparating chamber being the inner wallof the refrigerating chamber orbeing common to the separating and refrigerating chambers.

The refrigerating chamber has an inlet connection I5 provided with aport having a downwardly facing valve seat I6, this inlet connectionconnecting the lowerend of the refrigerating chamber with the inletchamber. The valve I1 carried by the lever I8 is adapted to close thisconnection I5 when the float I9 is in elevated position. i

This float I9 is ofthe inverted bucket type and has a restricted vent ordischarge hole at an elevated point in the top thereof. It will benoted" that the float embraces the inlet nipple 9 so that the incomingrefrigerant or the refrigerantdeliveredfrom` theppe l is dischargedinteriorly of the float. Gaseous refrigerantand/or air at this pointwill collect at the topof the inverted float while the liquidrefrigerant communicates freely with the interior .ofy chamber 6 throughan opening or openings lili at the bot- `tom of ^thefloat. i

The separating chamber has an air discharge connection 2I at the top`thereof and is provided withV a downwardly facing valve seat 22 with aowhich the valve 23 cooperates. This valve 23 is provided with a float24, the arm 25 of which is` pivoted at 26, the valve being connectedthereto at 21 so that when* the iloat is lifted by liquid within theseparating chamber it closes the valve, 35

e' the fioat` acting as a weight to open the valve` when the `liquidlevel is below the oat actuating point.

A gauge glass 29 is provided, this being ccnnected to the upper end ofthe separating chamber by the valve connection 30 and to the inletchamber by the valve connection 3|. This gauge glass is a matter ofconvenience in setting the apparatus -into operation and also it enablesone to determine the liquid level in the separating chamber. e i l Therefrigeratlng chamber is provided with a discharge connection 32 whichdelivers to the evaporating coils, the `connection being preferablyprovided with a valve 33.

The air discharge 2| has a. valve 34 and delivers into the atmosphere orinto a Jar indicated at 35 which is of `advantage in inspecting adischarge.

To insure that the refrigerant discharged or tor 36 which is arranged sothat a relatively narrow passage or opening 3'I is provided therearound,as shown in `iligs. 2, 3 and 4. This substantially increases theefficiency of the apparatus although it will operate without suchfeature.

In the installation shown in Fig. 5, the receiver 38 is connected to thecondenser by the line 39 and to the evaporating' coils 3 through thepressure regulating valve 4U. The inlet pipe 1 of the purging apparatusis connected to the top of the receiver 3B by the connection 4I having avalve 42 therein and to the bottom of the receiver through theconnection 43 having the valve 44 therein. This structure is the same asthat described.

Referring to the installation shown in Fig. 5, the purger may be set inoperation as follows. Assuming it to be empty or undercharged, and withthe valves 44, 42, 33 and 34 closed, in this condition, the bucket floatI9 will be down or in valve opening position as shown in the drawingsand the float 24 will also be down or in valve opening position. The rststep is to open the valve 44, reference being had to Fig. 5, allowingthe purger to become primed or partially lled with liquid refrigerant.The liquid level inside the purger will fill the apparatus to a pointsubstantially above the normal level and liquid refrigerant will passthrough the inlet chamber to the refrigerating chamber, lling thisnormally to a substantially higher level than the level within theseparating chamber, the level in the refrigerating chamber dependingupon the condenser pressure as well as the position of valve 33. Thereason that the refrigerator chamber levelwill normally be higher thanthe separating chamber level is that the refrigerating chamber normallycontains less air to begin with than the separating chamber andfurthermore there is normally more storage capacity for compressed airin the line to valve 33 in practice than there is in practice in theline to valve 34 from the separating chamber. Condenser pressure governsthe extent to which the air ,above the liquid levels is compressed, butthe location of valves 33, 34 is a factor in the relative height of thelevels in the refrigerating and separating chambers. For example, ifvalve 33 should be four or ve feet from the purger, all of the air thatwas originally in the refrigerating chamber, as well as some of the airfrom the inlet chamber, can easily be compressed so that it will becontained in such a length of pipe between the purger and the valve.However, if valve 33 is only a few inches from the purger, there will beless pipe space available for storing the air when it is compressed whenliquid refrigerant first enters the unit. The same remarks also apply tothe location of valve 34 and the liquid level obtaining in theseparating chamber; i. e., it is dependent upon the condenser as well asthe location of valve 34.

When the purger is primed or partially filled with liquid, the valve 44is closed, shutting off the supply of liquid refrigerant and the valve42 is opened, preferably fully, connecting the purger to the top ofreceiver 38 and the gaseous refrigerant therein. The discharge valve 33is then cracked or opened slowly. This will allow the pressure in therefrigerating chamber I3 to drop to suction pressure and cause theliquid refrigerant therein to boil. Additional liquid refrigerant willpass into the refrigerating chamber through its inlet connection or portI5 slightly lowering the pressure in inlet chamber 5 and separatingchamber II, which in turn allows refrigerant gas and air from thereceiver to enter the inlet chamber and collect in the inverted bucketfloat I9. This element is thereby caused to float and rise, closing theliquid discharge valve I'I, i. e., the inlet valve to the refrigeratingchamber. In this condition, the interior of the purger will be at highor condenser pressure, whereas the liquid refrigerant in therefrigerating chamber will be boiling under low or suction pressure. Theboiling liquid refrigerant in the refrigerating chamber will thus chillthe liquid in the separating chamber to within a few degrees of lowpressure or suction temperature.-

In this condition, the refrigerant gas and air passing through thebucket vent 20 will rise through the liquid in the purger and, strikingagainst the baille 36, will be diverted against the refrigerated orchilled wall of the separating chamber. Since this gas is undercondenser pressure but at a decidedly lower temperature, the refrigeranttherein will condense and the non-condensable air component thereof willcollect in the top of the separating chamber. As the air collects,increasing the pressure on the liquid refrigerant in the separatingchamber, the refrigerant level will be lowered as can be observedthrough the gauge and the liquid thereby displaced will enter theinverted bucket float, causing it to sink and open the inlet connectionor port I5, thus discharging the displaced liquid to the refrigeratingchamber I3. When this has happened, refrigerant gas and/or air willagain enter the inlet chamber and collect in the inverted bucket floatcausing it to rise and close port I5.

When a substantial quantity of air has been accumulated in the foregoingmanner in the dome or top of the separating chamber II, the airdischarge valve 34 may be opened and with further lowering of the liquidlevel due to accumulation of compressed air as described above, the ballfloat 24 drops, opening the air valve and discharging air from thepurger through air discharge connection 2l to the atmosphere or intoinspection jar 35. The valve 44 is then cracked or opened slowly toallow enough liquid refrigerant from the receiver 38 to reach the purgerto maintain the desired liquid level for the refrigerating chamber (inpractice indicated by the frost level on the outside of the purgercasting or on pipe 32, which is caused by condensation and freezingthereon of moisture from the air. Preferably an amount should beadmitted sufficient to keep the refrigerating chamber practically filledwith boilingA refrigerant). Thereafter, the operation of the purger iscontinuous and automatic. The gaseous refrigerant is caused to condensewhen it strikes the cold wall of the separator chamber, freeing the airin the mixture, which collects in the dome and oper'- ates the airventing float valve in the manner described. After all the air has beenpurged from the system, it is not necessary to close any of the valvesor remove the unit from the line.

Assuming at the start that the valves 8, 33, and 34 are closed, toplacethe unit of Fig. 1 in operation as a combination expansion Valveand purger, the valve 8 is rst opened until the purger is primed withliquid refrigerant as indicated by the liquid level in the gauge glass.The valve 33 is then opened slowly, reducing the pressure in therefrigerating chamber to substantially the same pressure as exists inthe evaporator.

This *reduction` in pressure causesthe liquid refrigerant to boilands-chill the" wall I4 separating the reirigerantfchamber and theseparating chamber. Any refrigerant gas` that passes `through theventinthe inverted `bucket oat release mechanism. Liquid refrigerantwill enter i the inlet chamber through connection 'l asmfast as itis`c`ondensed in the condenser 2. As ,the liquid refrigerant enters` the`inverted bucket float due to the abovedepressicnof the liquid level,the float loses its buoyancy and sinks, opening valve l I5 andVdischarging theliquid to the refrigerating r vchamber. jAs`refrigerating liquid isdischarged to lthe refrigerating chamber, morerefrigerant gas mixed withtheair willenterlthe inverted bucket floatcausing the float to rise `and close s valvelBi This cycle is repeatedasfreqjuently as desired to; discharge the liquid refrigerant fromthecondenser tothe refrigerantchamber and then directlyto theevaporator. In addition to the. refrigerant condensedv in the" regularcondenser,` all refrigerant gas condensed in the sepa# ratingchamberVwill `also be discharged `through valve 15 `to the refrigerantto the evaporator.`

My purging! apparatus is continuous in operation and when' onceinstalled isautomatic-that is, no other manipulation of the controlvalves is required. `The `amount of gas to be purged may be governedibythe size of thelventing opening in the bucket and thestatichead thatforces the gas through the venting opening. The`size of thisventingfopening can bereadily determined for each type"of refrigerant.`The amount ofgas that should s pass through the venting opening shouldbe slightly less than the condensing capacity of the heat exchange"surface of ,the separating chamber, Therefore, it isimpossible to feedthe purger too much gas, and also, it willwork `at l maximum efficiencybecause nothing less than `the l maximum amount ofv gas can befed tothepurgf ing'unit. Whenfused as acombination'expansion valve and purgerit serves a double function. It should be stated `thatfthis applicationis possible only when allcof theliquid refrigerant is carried on the lowpressure or evaporator side of the sys` tem. The inverted bucketmechanism described discharges the liquid refrigerantto the evaporatorjust as fast as it is formed `in the condenser. Anyv air that is in thesystem or that may be introduced into `the system due to low, suctionpressures or while charging the svstemfwith additional refrigerant will"automatically be `vented `from the purger without attentionon the partofthe engl-l I have mediated aidldeseribea abraetiarem;

bodimentcf my invention in two installations. vIl have not illustratedcertain` modifications ,1in

structure that @are pSSible ortheir 'v riousnstalvung adaptations as, itis believedmettais-disciov l sure will enable those'skilledin'theariitoembodyl 1 "sx'n'adaptr myirnprovements.a'slmybCeSirec'i.'l

Having thus described @my inventivanj,A what I i claim as newahddesifeto secureby LettersfPatf I`1,1SI' l, y s j c i.. 1.Ir`1a.purging` apparatus `for refrigerating s systems,` `the combination ofan inlet chamber having fa refrigerant-"supply` connection `at the lowerend thereof provided with Jva v return check chamber and thencevconstituting a refrigerating chamber for said separating` chamber, saidrefrigerating chamber having a discharge connection at the top thereofand being provided with an inlet port openingto saidinletchamber andhavinga downwardly facing valve seat, an upwardly closing` valvecoacting with said valve seat, an inverted bucket float having arestricted vent opening in the top thereof` arranged `in said inletchamber` to embrace said supply` connection thereof and `operativelyassociated with said valve, an air discharge port at the top pf saidseparating chamber provided with a downwardly` facing valve seat, anupwardly seating valve operatively associated with said air dischargeport, and a float in said separ- `ating chamber operatively associatedwith said air Yvalve and acting to close the same when the level of theliquid in the separating chamber is sufficient to sustain the float invalve closing position, the float acting as a weight to open the valvewhen the level of the liquid is such that it ,said inlet chamber, avalve for said inlet connection, an inverted bucket float operativelyassociated with said valve and having a restricted -ventopening at thetop thereof, said bucket float being arranged in saidinlet chamber toreceive the refrigerant and `refrigerant gas delivered thereto, an airdischarge valve at the top of said "separating chamber, and a float insaid separatw ing chamber operatively associated with said air valve andacting to close the same when thelevel ofthe liquid in the separatingchamber is `reutlicient` to sustain the float in valve closing position.3. In` a: purging `apparatus for refrigerating systems, the combinationof an inlet chamber having a refrigerant `supply connection, aseparlating chamber above and opening to said inlet chamber and providedwith a jacket constituting a `refrigerating chamber for said separatingchamber, said `refrigerating chamber having a discharge connection andhaving an inlet con`` nectionto said inlet chamber, a valve for saidin-y let connection, a float `in said inlet chamber operativelyassociated `withsaid valve, a deliector disposed at thelower end oi saidseparating chamn ber to deflect therefrigerant passing from the inletchamber `into the separating chamber r thefloat in valve closingposition.

C 14.111,9, purging apparatus for` refrigerating systems, thecombinationof a separating charni f ber provided with a jacket constituting arefrigerating chamber for saidseparating chamber, saidrefrigeratingchamber having a discharge connection and an inletconnection, an air dis-n charge valve at the topof said separating chamber, and a float in said separating chamber operatively associated Withsaid air valve and acting to close the same when the level of the'liquidin 75 the separating chamber is sufficient to sustain the float in valveclosing position.

5. In a purging apparatus, the combination of an inlet chamber having arefrigerant supply connection, a separating chamber in communicationwith said inlet chamber to receive refrigerant therefrom, arefrigerating chamber for said separating chamber, said refrigeratingchamber having a discharge connection and an inlet valve, a ventedbucket float disposed to receive the refrigerant deliveredto said inletchamber, said float being operatively connected to said refrigerantchamber inlet valve, an air discharge valve for said separating chamber,and a oat in said separating chamber operatively connected with said airvalve and acting to close the same when the level of the liquid in theseparating chamber is at or above a predetermined level.

6.1m a purging apparatus, the combination of an inlet chamber having arefrigerant supply connection, a separating chamber in communicationwith said inlet chamber to receive refrigerant therefrom, arefrigerating chamber for said separating chamber, said refrigeratingchamber having a discharge connection and an inlet valve, a floatdisposed in said inlet chamber and operatively connected to saidrefrigerating chamber inlet valve, an air discharge valve for saidseparating chamber, and a float in said separating chamber operativelyconnected with said air valve and v4acting to-close the same when thelevel of the liquid in the separating chamber is at or above apredetermined level.

7. In a purging apparatus, the combination of an inlet chamber having asupply connection, a separating chamber in communication with said inletchamber to receive liquid and gas therefrom, cooling means for saidseparating chamber, a oat disposed in said inlet chamber, a liquiddischarge valve for said inlet chamber operatively associated with said'float to control the discharge of the liquid from said inlet chamber inaccordance with the position of said oat, an air discharge valve forsaid separating chamber, and a float in said separating chamberoperatively associated with said air discharge valve.

8. In a purging apparatus, a chamber having an opening for admitting aliquid refrigerant and a gaseous refrigerant mixture containing air tothe chamber, a float associated with said opening and adapted to collectsaid gaseous mix- -ture and to be elevated thereby in said liquid,

a refrigerating chamber having a portion common to said first namedchamber and having a connection to said chamber, and valve means forsaid connection controlled by said oat to admit liquid refrigerant fromsaid first named chamber to said refrigerating chamber when the oat islowered, said refrigerating chamber having a valve controlled dischargeline to decrease the pressure in the refrigerating chamber when saidline is open and thereby cause liquid refrigerant in the refrigeratingchamber to boil and chill said common portion of the refrigerating andrst named chambers, said float having provision for slowly freeing saidgaseous mixture collected thereby, whereby said mixture arises intoContact with and is chilled by said chilled portion, the gaseousrefrigerant in the mixture condensing and the air collecting at the topof the first named chamber, resultant increase in air pressure in saidrst named chamber causing said float to bev depressed whereby said firstnamed connection is opened for entrance of liquid to said refrigeratingchamber.

9. In a purging apparatus, a purging chamber adapted to contain liquidrefrigerant and having a connection thereto for admitting a gaseousrefrigerant mixture containing air to the chamber, control meansassociated with said connection and adapted to collect said gaseousmixture admitted therethrough, a refrigerating chamber including aportion in heat transmitting relation to said first named chamber, saidrefrigerating chamber having an opening communicating with said firstnamed chamber' to admit liquid refrigerant thereto from the first namedchamber, a valve for said opening controlled by said control meanswhereby the opening is closed when the control means is elevated, saidrefrigerating chamber being adapted to have a relatively low pressurecreated therein to reduce the pressure suiciently to cause said liquidrefrigerant in the refrigerating chamber to boil and chill said portion,said control means having a vent therein for slowly venting said gaseousmixture into the first named chamber, said mixture arising above theliquid in said first named chamber and contacting said chilled portionwhereby the gaseous refrigerant condenses and air in the mixturecollects at the top of said chamber, increase in air pressure in saidchamber causing the liquid refrigerant to actuate said control meanswhereby said opening is exposed for entrance of liquid refrigerant and'condensate to said refrigerating chamber, and means for removing airfrom said first named chamber.

10. In a purging apparatus, a purging chamber ladapted to contain liquidrefrigerant andhaving a connection thereto for admitting a gaseousrefrigerant mixture containing air to the chamber, a hollow floatassociated with said connection and adapted to collect said gaseousmixture admitted therethrough and to be elevated thereby in liquidrefrigerant contained in the chamber, a refrigerating chamber having awall common to said first named chamber and having an openingcommunicating with said first named chamber to admit liquid refrigerantthereto from the rst named chamber, a valve for said opening controlledby said float whereby the opening is closed when the float is elevated,said refrigerating chamber being adapted to have a relatively lowpressure created therein to reduce the pressure in the refrigeratingchamber sufficiently to cause said liquid refrigerant to boil and chillsaid wall, said float having a vent therein for slowly venting saidgaseous mixture from said float into the first named chamber, saidmixture arising above the liquid in said rst named chamber andcontacting said chilled Wall Whereby the gaseous refrigerant condensesand air in the mixture collects at the top of said chamber,

increase in air pressure in said chamber causing the liquid refrigerantto enter said float whereby the latter sinks and said valve lis actuatedto expose said opening for entrance of liquid refrigerant and condensateto said refrigerating chamber, and means for removing 'air from saidchamber.

1l. In a purging apparatus, the combination of a chamber having anopening for the admission of a gaseous refrigerant mixture containingair thereto, said chamber being also adapted to receive a quantity ofliquid refrigerant, a hollow vented float member disposed in the liquidin said chamber adjacent said opening, said member being adapted tocollect said gaseous mixture admitted to the chamber and to be elevatedthereby in said liquid refrigerant, means for chilling at least aportion of the wall of said, chamber, the vent in said oat member slowlyventing said gaseous mixture from the float member, said vented mixturearising above the liquid in said chamber and contacting said chilledportion whereby the gaseous refrigerant eondenses and air in the mixturecollects at the top of the chamber to thereby depress the level of theliquid, said chamber having an air discharge opening, and means coastingwith said last named opening to vent the collected air from 5 thechamber.

THOMAS H'. REA.

